Definitions for visual meteorological conditions

Here are all the possible meanings and translations of the word visual meteorological conditions.

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Visual meteorological conditions

In aviation, visual meteorological conditions is an aviation flight category in which visual flight rules flight is permitted—that is, conditions in which pilots have sufficient visibility to fly the aircraft maintaining visual separation from terrain and other aircraft. They are the opposite of Instrument Meteorological Conditions. The boundary criteria between IMC and VMC are known as the VMC minima and are defined by: visibility, cloud ceilings, and cloud clearances.
The exact requirements vary by type of airspace, whether it is day or night, and from country to country. Typical visibility requirements vary from one statute mile to five statute miles. Typical cloud clearance requirements vary from merely remaining clear of clouds to remaining at least one mile away from clouds horizontally and one thousand feet away from clouds vertically. For instance, in Australia, VMC minima outside controlled airspace are clear of cloud with 5,000m visibility below 3,000ft AMSL or 1,000ft AGL, and 1,000ft vertical/1,500m horizontal separation from cloud above these altitudes or in controlled airspace. Above 10,000ft, 8,000m visibility is required to maintain VMC. Air Traffic Control may also issue a Special VFR clearance to VFR aircraft, to allow departure from a control zone in less than VMC - this reduces the visibility minimum to 1,600m.

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visual meteorological conditions

Weather conditions in which visual flight rules apply; expressed in terms of visibility, ceiling height, and aircraft clearance from clouds along the path of flight. When these criteria do not exist, instrument meteorological conditions prevail and instrument flight rules must be complied with. Also called VMC. See also instrument meteorological conditions.